Price::checkRequiredFieldsModify

public function checkRequiredFieldsModify($fields)
{
	$r = new Result();

	$listFieldsInfoAdd = $this->getListFieldInfo($this->getFields(), ['filter'=>['ignoredAttributes'=>[Attributes::HIDDEN, Attributes::READONLY], 'ignoredFields'=>['PRODUCT_ID']]]);
	$listFieldsInfoUpdate = $this->getListFieldInfo($this->getFields(), ['filter'=>['ignoredAttributes'=>[Attributes::HIDDEN, Attributes::READONLY, Attributes::IMMUTABLE]]]);

	foreach ($fields['PRODUCT']['PRICES'] as $k=>$item)
	{
		$required = $this->checkRequiredFields($item,
			$this->isNewItem($item)? $listFieldsInfoAdd:$listFieldsInfoUpdate
		);
		if(!$required->isSuccess())
		{
			$r->addError(new Error('[prices]['.$k.'] - '.implode(', ', $required->getErrorMessages()).'.'));
		}
	}
	return $r;
}